Interfacial Liquid Water on Graphite, Graphene, and 2D Materials

Abstract

The optical, electronic, and mechanical properties of graphite, fewlayer, and two-dimensional (2D) materials have prompted a considerable number of applications. Biosensing, energy storage, and water desalination illustrate applications that require a molecular-scale understanding of the interfacial water structure on 2D materials. This review introduces the most recent experimental and theoretical advances on the structure of interfacial liquid water on graphite-like and 2D materials surfaces. On pristine conditions, atomic-scale resolution experiments revealed the existence of 1−3 hydration layers. Those layers were separated by ∼0.3 nm. The experimental data were supported by molecular dynamics simulations. However, under standard working conditions, atomic-scale resolution experiments revealed the presence of 2−3 hydrocarbon layers. Those layers were separated by ∼0.5 nm. Linear alkanes were the dominant molecular specie within the hydrocarbon layers. Paradoxically, the interface of an aged 2D material surface immersed in water does not have water molecules on its vicinity. Free-energy considerations favored the replacement of water by alkanes.

Ion and water adsorption to graphene and graphene oxide surfaces

“…36 However, electron microscopy typically cannot yield molecular-scale information about the liquid phase and has not been sufficient to characterize water layering. 28 High-resolution atomic force microscopy (AFM) can provide molecular-scale information about solid–liquid interfaces 37 and three-dimensional AFM works have detailed water structure near graphene, as covered in detail elsewhere. 28 Briefly, a three-dimensional AFM work on pristine graphite 38 demonstrated water layering with an interspace distance of 3 Å, in good agreement with prior high-resolution XR studies.…”

“…flow behavior and hydrophobicity, properties. 28 Evidently, understanding contamination is imperative for reconciling differences in experimental data. Experimental methods that provide chemical information can be useful to distinguish contamination at the graphene–water interface from other components, as will be discussed in detail later.…”

“…In particular, three-dimensional AFM can yield high-resolution information, approximately a few Å, about both the graphene and water structure at solid-liquid interfaces, described in detail by Garcia in a recent review. 28 Brewster angle microscopy (BAM) is an in situ technique used to image surfactants suspended on liquid surfaces that can provide structural information with µm lateral resolution. 29 Vibrational sum frequency generation spectroscopy (SFG) is a nonlinear, interface-specific technique that can examine water organization near graphene, GO, and other surfaces (Fig.…”

Variation of Critical Crystallization Pressure for the Formation of Square Ice in Graphene Nanocapillaries

“…Thus, the existence of low-dimensional ice can be facilitated or suppressed by the design of capillary length in practical applications, according to the interrelation between the length of the capillary and critical crystallization pressure. This study provides physical insights about the variation mechanism of critical crystallization pressure for the square ice formation, and widespread applications in many fields such as nanomaterial, 42 nanofluidic, 42,43 and nanotribology. 44 ■ COMPUTATIONAL METHODS Molecular Dynamics Simulation.…”

Effect of terahertz electromagnetic field on single-file water transport through a carbon nanotube

“…In recent years, the distinctive structural and kinetic characteristics of water confined in nanoscale environments have been observed in certain complex and biological protein channels, demonstrating significant disparities from those of bulk water. 1,2 The rapid conduction of single-file water chains in one-dimensional channels as well as the regular structure of quantized water layers in two-dimensional channels has sparked vast interest in research. 3,4 Hence, the investigation of water transportation mechanisms within nanochannels holds significance for fundamental scientific research and various industrial, biological, and medical applications.…”